Access control may have competing security objectives and convenience objectives. The security objectives may include ensuring that only authorized personnel are granted access to a secured resource, and that the access control procedure is not easily circumvented. The convenience objectives may include reducing the time, effort, and actions taken by an individual to complete the access control procedure. The convenience is reduced with each additional amount of time a user spends waiting for access, and with each additional action that the user has to perform to gain access.
Smartcards and proximity cards provide more security and convenience than physical keys, but still require the user to carry one additional item (e.g., the smartcard or proximity card) and still require the individual to retrieve and place the smartcard or proximity card in front of a reader before access can be granted. While harder to replicate than physical keys, smartcards and proximity can also compromise security, because they can be used by anyone when misplaced, and can be replicated with the right equipment.
Smartphones are ubiquitous, and can be more secure than smartcards and proximity cards due to biometric authentication, passwords, personal identification numbers (“PINs”), or other authentication that may be required before the smartphone can be used for access control or other purposes. However, the convenience of using a smartphone for access control is compromised when having to physically remove a smartphone from a purse or pocket, securely unlock the device via the biometric authentication, password, PIN, or other authentication, perform one or more interactions to initiate an unlock procedure, and wait some amount of time for wireless authorization to complete.